This weekend, the ACC is coming to Chicago. No, not the home of the Midwest bracket's Sweet 16. This ACC -- the American College of Cardiology -- will feature doctors presenting clinical trial data, not UNC knocking down jump shots. Let's see what investors can expect from this weekend's blood-pumping scientific meeting.

Front and center
From a media standpoint, the highlight of the conference will be Merck's (NYSE: MRK) and Schering-Plough's (NYSE: SGP) full presentation of their Enhance trial data. But from an investor's perspective, I'm not sure the presentation will mean much.

The most important information for investors has already been released. Vytorin, a combination of Zetia and Zocor, didn't lower the amount of plaque in a neck artery more than Zocor alone. Merck makes Zocor, but it's available as a generic, so the data argues that patients would be just as well off taking generic Zocor, or another statin such as Pfizer's (NYSE: PFE) Lipitor and AstraZeneca's (NYSE: AZN) Crestor.

The good news is that Vytorin still lowered bad cholesterol more than Zocor. The duo will thus try to argue that plaque buildup in arteries of familial hypercholesterolemia (FH) patients -- the ones used in the Enhance trial, who have unusually high cholesterol levels -- is no longer a valid indicator of whether a drug works, because FH patients are getting better care now than when a similar trial worked for Lipitor.

The ultimate test for Vytorin will be whether the drug lowers patients' chances of heart attacks and other cardiac events. Unfortunately, that data won't be available for a few years, so expect the duo's PR people to be in full swing this weekend.

Big man getting leaner
The full results of the Enhance trial won't be the only big event. Docs will also be presenting data from clinical trials on obesity drugs.

Data on Merck's taranabant has leaked out, suggesting that the lower dose of the drug didn't meet the 5% weight-loss threshhold that the company likely needs to gain FDA approval. The higher dose shed sufficient pounds, but reportedly caused side effects -- depression and suicidal thoughts -- which would make it unlikely to gain FDA approval. A similar drug, Sanofi-Aventis' (NYSE: SNY) Acomplia, was denied approval last year because of similar side effects.

If the data is true -- Merck isn't saying, since the data from the meeting is embargoed -- taranabant's downfall could be a boon to drug companies that are farther behind Merck in developing obesity drugs, such as Amylin Pharmaceuticals (Nasdaq: AMLN).

Data from a trial examining Acomplia's affect on patients with hardened arteries will also be presented at ACC. While I doubt the results of the trial will convince the FDA to look past the psychotic side effects, the trial could affect sales of Acomplia in Europe, where it is already approved.

The sixth man
Interestingly, the ACC can attract studies on a fairly random assortment of drugs. They're not really heart drugs, but their use can have an indirect effect on the heart, justifying their appearance at the big dance.

For instance, one group is presenting a meta-analysis of the cardiovascular risk of Pfizer's arthrisus treatment Celebrex. The problem with meta-analyses -- pooling data from multiple clinical trials -- is that they're usually a no-win situation for the companies. If the pooled data turns up nothing, the drugs rarely get a sales boost, but if increasing the number of patients makes a side effect statistically significant, the drugs sales can be hurt substantially. Such was the case with Dr. Steven Nissen's study of GlaxoSmithKline's (NYSE: GSK) Avandia.

Speaking of Dr. Nissen, in an interesting head-to-head competition, he'll present data from a clinical trial pitting diabetes drug Actos from Takeda Pharmaceutricals against Sanofi-Aventis' Amaryl, which is available as a generic. The data will look at hardening of arteries, which is accelerated in diabetic patients.

Get out your foam finger
O.K., so you probably won't be tailgating in the parking lot of McCormick Place this weekend. Still, drug stock investors should be on the outlook for weekend press releases synopsizing the data -- between basketball games, of course.